Organ transplantation and cancer chemotherapy are life-saving interventions for an increasing number of patients. Despite important advances in surgical technique, immunosuppressive regimens, and the development of novel antimicrobial agents, these immunocompromised hosts remain at substantial risk for developing infections. Care of this complex patient population requires unique knowledge that differs from that of the general Infectious Diseases clinician. Accordingly, Transplant Infectious Diseases has emerged as a subspecialty within the field of Infectious Diseases (ID), and the American Society of Transplantation has developed a core curriculum for training specialists in Transplant ID. Duke University is uniquely poised to provide fellows with exceptional training in Transplant ID: Duke University Hospital is a major transplant and cancer care center with an active Transplant/Immunocompromised Host ID Service, ACGME-accredited Training Programs in ID and Medical Microbiology, and a highly qualified faculty committed to teaching fellows in the specialized area of Transplant ID including state-of-the-art methods of basic science and patient- oriented research. In fact, with minimal support over the past 10 years, the Duke ID Division has trained several successful young faculty who currently hold academic positions, specializing in Transplant ID care and research. The objective of this Training Program is to capitalize on the rich resources available at Duke in order to develop innovative ID physician-scientists trained in the care of immunocompromised hosts and the latest research methods. The combined research and clinical training program will occur after completion of at least one year of general clinical ID fellowship, which will include baseline Transplant ID experience. The Transplant ID core curriculum will include additional training in the clinical care of the transplant/immunocompromised host, training in laboratory medicine relevant to Transplant ID, and development of either basic or clinical research skills individualized to the trainee's expertise and career goals. Key areas for research training, as applicable to the Transplant/Immunocompromised host, will include: 1) laboratory medicine, 2) microbial epidemiology & pathogenesis, 3) host susceptibility & response to infection, and 4) medical management & treatment outcomes.